Control systems are required for controlling the positioning or movement of various devices which can operate in any direction in a plane. That is, movement may be required along a first axis, or along a second axis at right angles to the first axis, or along any line between the axes. One application for such a control is in a motor driven wheelchair or cart having two motors for respectively driving the two wheels of the chair, as described and claimed in U.S. Pat. No. 3,100,860, issued Aug. 13, 1963 to Harry Rosenthal. In this drive, a joy stick operator controls an actuator which operates four leaf switch assemblies to control the direction and speed of the two motors to propel the chair in any direction within the plane. Although this drive control has been highly satisfactory in use, it has the objection of any electrical switch apparatus that the contacts deteriorate with use, and that the speed control provided by operation of the various leaves of the switches produces step changes in speed, rather than a continuous change. Auxiliary controls can be used to provide continuous variations in speed, but this has the objection that a different actuator is required for the auxiliary controls. Further, the structure must be relatively large to provide the degree of control which is desired, and an auxiliary speed control further increases the size of the unit.
A multi-axis control system is required for other applications, such as in an audio system for controlling the volume and/or tone, and for controlling the balance in a multichannel system.